1. Field of the Invention
The invention relates generally to cathode ray tube display terminals and more particularly to the modularized design of the terminal including a pluggable power supply and a means for unplugging the power supply without overloading the electronic components.
2. Description of the Prior Art
Many data processing systems have a cathode ray tube (CRT) display as an element of an operator's console. This display is integrated mechanically into a central processor and may have a separate power supply built into the console or may have power provided from the central power source in the central processor. The Honeywell Level 64 data processor is typical of such a system.
Data processing applications are expanding more and more from batch processing to on-line processing. In batch processing applications, an operator at the operator's console controls the data processor. In on-line processing, a number of CRT display terminals may be coupled to a data processing system via communication lines. An operator at each terminal has access to the data processor.
The need for CRT display terminals has proliferated making the field more competitive for the manufacturer of terminals, thereby requiring the terminals to be more cost effective in the product and maintenance areas.
The prior art CRT display terminals were an integrated design. The power supply was wired into the terminal making trouble shooting and parts replacement costly. In order to make trouble shooting and repair less costly, the elements of the CRT display terminal were modulated and were made pluggable. This enabled the customer at a remote site to make temporary repairs by replacing elements thus eliminating a repair service call. The power supply was made pluggable. A single finger hole was molded into the power supply for grasping the power supply in order to remove it. This solution, however, presented some problems. Excessive force for one finger was required to remove the power supply. Also, if the power supply was removed when the display terminal was in a "Power On" condition, there was a possibility that the electrical components would be damaged.